Start Flutter update

lib/ui/widgets/post_create_form_widget.dart

@@ -1,4 +1,3 @@
-
 import 'package:comunic/enums/post_kind.dart';
 import 'package:comunic/enums/post_target.dart';
 import 'package:comunic/enums/post_visibility_level.dart';
@@ -12,7 +11,7 @@ import 'package:comunic/utils/files_utils.dart';
 import 'package:comunic/utils/intl_utils.dart';
 import 'package:comunic/utils/post_utils.dart';
 import 'package:comunic/utils/ui_utils.dart';
-import 'package:file_picker_cross/file_picker_cross.dart';
+import 'package:file_picker/file_picker.dart';
 import 'package:flutter/material.dart';
 import 'package:image_picker/image_picker.dart';
 
@@ -278,15 +277,18 @@ class _PostCreateFormWidgetState extends State<PostCreateFormWidget> {
   /// Pick a PDF for the new post
   Future<void> _pickPDFForPost() async {
     try {
-      final picker = await FilePickerCross.importFromStorage(
-        type: FileTypeCross.custom,
-        fileExtension: "pdf",
+      final file = await FilePicker.platform.pickFiles(
+        type: FileType.custom,
+        allowedExtensions: ["pdf"],
+        withData: true,
       );
 
+      if (file == null || file.files.isEmpty) return;
+
       _resetPostSelection();
 
       setState(() {
-        this._postPDF = picker.toUint8List();
+        this._postPDF = file.files.first.bytes;
       });
     } catch (e, stack) {
       print("Pick PDF error: $e\n$stack");

lib/ui/widgets/safe_state.dart

@@ -8,8 +8,8 @@ import 'package:flutter/material.dart';
 /// @author Pierre HUBERT
 
 abstract class SafeState<T extends StatefulWidget> extends State<T> {
-  final _subscriptions = List<StreamSubscription>();
-  final _timers = List<Timer>();
+  final _subscriptions = <StreamSubscription>[];
+  final _timers = <Timer>[];
 
   bool _unmounted = false;
 

lib/ui/widgets/tablet_mode/user_page_tablet.dart

@@ -123,7 +123,7 @@ class _UserPageTabletState extends State<UserPageTablet> {
               // Friends list of the user
               _userInfo.isFriendsListPublic
                   ? Expanded(
-                      child: OutlineButton.icon(
+                      child: OutlinedButton.icon(
                         onPressed: () => MainController.of(context)
                             .openUserFriendsList(_userInfo.id),
                         icon: Icon(Icons.group),

lib/ui/widgets/text_rich_content_widget.dart

@@ -27,7 +27,7 @@ class TextRichContentWidget extends StatelessWidget {
   static List<TextSpan> _parse(String text, TextStyle style) {
     if (style == null) style = TextStyle();
 
-    List<TextSpan> list = List();
+    List<TextSpan> list = [];
     String currString = "";
 
     text.split("\n").forEach((f) {

lib/ui/widgets/text_widget.dart

@@ -55,7 +55,7 @@ class TextWidget extends StatelessWidget {
   List<InlineSpan> _parseLinks(
       BuildContext context, String text, TextStyle style) {
     var buff = StringBuffer();
-    final list = new List<InlineSpan>();
+    final list = <InlineSpan>[];
 
     // Change word function
     final changeWordType = () {

lib/ui/widgets/user_writing_in_conv_notifier.dart

@@ -27,7 +27,7 @@ class _UserWritingInConvNotifierState
     extends SafeState<UserWritingInConvNotifier> {
   final _usersInfo = UsersList();
 
-  final _list = List();
+  final _list = [];
 
   @override
   void initState() {